1. Field of the Invention
The present invention relates to an apparatus of fabricating a liquid crystal display, and more particularly to a unified strip/cleaning apparatus wherein a strip device is unified with a cleaning device.
2. Description of the Related Art
Generally, since a liquid crystal display (LCD) has the advantages of small size, thin thickness and low power consumption, it has been used for a notebook personal computer, office automation equipment and audio/video equipment, etc. Particularly, an active matrix LCD using thin film transistors (TFT""s) as switching devices is suitable for displaying a dynamic image.
An active matrix LCD displays a picture corresponding to a video signal such as a television signal on a picture element or pixel matrix having pixels arranged at each intersection between gate lines and data lines. Each pixel includes a liquid crystal cell controlling a transmitted light amount in accordance with a voltage level of a data signal from the data line. The TFT is installed at each intersection between the gate lines and the data lines to switch the data signal to be transmitted to the liquid crystal cell in response to a scanning signal from the gate line.
FIG. 1 shows a TFT formed on a substrate 18. A process of fabricating the TFT will be described below. First, a gate electrode 20 and a gate line is deposited on the substrate 18 with a metal such as Al, Mo, Cr or their alloy, etc. and thereafter is patterned by the photolithography. A gate insulating film 22 made from an organic material such as SiNX or SiOX, etc. is deposited on the substrate 18 provided with the gate electrode 20. Then, a semiconductor layer 24 made from an amorphous silicon (a-Si) layer and an ohmic contact layer 26 made from an a-Si doped with n+ ions are continuously deposited on the gate insulating film 22. A source electrode 28 and a drain electrode 30 made from a metal such as Mo or Cr, etc. are formed on the ohmic contact layer 26. The source electrode 28 is patterned integrally with the data line. The ohmic contact layer 26 exposed through an opening between the source electrode 28 and the drain electrode 30 is eliminated by dry etching or wet etching. A protective film 32 made from SiNX or SiOX is entirely deposited on the substrate 18 to cover the TFT. Subsequently, a contact hole is formed in the protective film 32. A pixel electrode 34 made from an indium tin oxide (ITO) is coated so as to be connected, via the contact hole, to the drain electrode 30. Such a TFT fabricating process includes a photoresist pattern formation step, an etching step and a photoresist pattern strip step, etc. upon the patterning of the electrode layers 20, 28 and 30 or upon the formation of the contact hole.
FIG. 2 shows a conventional strip and cleaning apparatus. Referring to FIG. 2, the conventional strip and cleaning apparatus includes a loader 40 for loading a cassette (not shown) received with a substrate, a strip line for removing a photo-resistor (PR) of the substrate transported from the cassette, a cleaning line for cleaning the stripped substrate, a dry module 54 for drying the substrate cleaned by means of the cleaning line, and a unloader 56 for loading the substrate dried by means of the dry module 54 into the cassette that is arranged in an inline type. The loader 40 carries the substrate received in the cassette (not shown) into a first strip module 42 using a conveyor or a robot. The substrate from the loader 40 in which the PR formed on the TFT is removed by a pipe shower at the first strip module, is conveyed into a second strip module 44. A stripper made from a mixture of H3PO4, CH3COOH and HNO3 is used to remove the PR on the substrate. The second strip module 44 removes residual PR film that has not been removed at the first strip module 42 using a brush. The substrate having the PR film removed by physical cleaning is carried into a third strip module 46. The third strip module 46 injects the stripper at a high pressure by a cavitation jet (CJ) system to remove the residual PR film on the substrate that has not been removed at the first and second strip modules 42 and 44. The substrate stripped at the third strip module 46 is carried into an isopropyl alcohol (IPA) injecting module 48. The IPA injecting module 48 removes minute alien substances and cleans the stripper using an IPA liquid. If the stripper and de-ionized water are mixed at a specific composition ratio, OH is produced to corrode aluminum (Al) formed on the surfaces of the source, drain and gate electrodes. Thus, the stripper is diluted with the IPA liquid so as to prevent the corrosion of aluminum. The substrate cleaned with the IPA liquid by means of the IPA injecting module 48 is carried into a first cleaning module 50. The first cleaning module 50 cleans the substrate by a pipe shower using de-ionized water and thereafter carries it into a second cleaning module 52. The second cleaning module 52 injects de-ionized water at a high pressure by the CJ system to clean the substrate. The substrate cleaned at the second cleaning module 52 is carried into a dry module 54. The dry module 54 rotates the substrate using a centrifugal force of 1800 to 2200 rpm to remove the de-ionized water. The substrate dried at the dry module is received into the cassette on the unloader 56.
Such conventional strip/cleaning equipment requires a wide installation space of 10840xc3x971800 mm.
Accordingly, it is an object of the present invention to provide a unified strip/cleaning apparatus wherein a strip line is integrated with a cleaning line to minimize the installation space.
In order to achieve these and other objects of the invention, a unified strip/cleaning apparatus according to an embodiment of the present invention includes a strip line for removing resin on a substrate; and a cleaning line provided under the strip line to clean and dry the substrate.